1. Technical Field
The present invention relates to liquid ejecting head units and liquid ejecting apparatuses, particularly to ink jet recording head units that discharge ink as liquid and ink jet recording apparatuses.
2. Related Art
A liquid ejecting apparatus is an apparatus that includes a liquid ejecting head capable of ejecting liquid as a droplet through nozzles and ejects various kinds of liquid from this liquid ejecting head. As an representative example of the liquid ejecting apparatus, for example, an image recording apparatus such as an ink jet recording apparatus (printer) or the like that includes an ink jet recording head (hereinafter, also called a “recording head”) and performs printing by ejecting a liquid ink as an ink droplet through a nozzle in the recording head, can be cited. In addition, the liquid ejecting apparatus is employed for ejecting various kinds of liquids such as coloring materials used in color filters of liquid crystal displays and the like, organic materials used in electro luminescence (EL) displays, electrode materials used in the formation of electrodes, and so on. A recording head of the image recording apparatus ejects a liquid ink, while a coloring material ejecting head of a display manufacturing apparatus ejects solutions of coloring materials of red (R), green (G) and blue (B). Further, an electrode ejecting head of an electrode material formation apparatus ejects a liquid electrode material, and a bioorganic matter ejecting head of a chip manufacturing apparatus ejects a solution of bioorganic matter.
Of the above-mentioned printers, such a printer is provided that is equipped with a recording head unit in which a plurality of recording heads are fixed to a support member (for example, see JP-A-2008-221745). Each of the recording heads is so configured as to introduce ink into a pressure chamber (pressure generation chamber) from an ink supply source such as an ink cartridge or the like, generate a change in pressure in the ink within the pressure chamber by activating a pressure generation unit such as a piezoelectric element, a heating element or the like, and eject the ink within the pressure chamber as an ink droplet through a nozzle that is opened in a nozzle surface by making use of the change in pressure. The support member is a plate-like member which is parallel to the nozzle surface of the recording head, and in which an opening portion is provided penetrating through in a plate-thickness direction thereof. Each of the recording heads is fixed to the border of the opening portion with a screw or the like while the nozzle surface thereof is exposed from the opening portion of the support member.
Recently, recording head units have been required to be smaller in size. However, in the above configuration, because the recording heads are fixed to the border of the opening portion of the support member, it has been difficult to miniaturize the recording head unit. In other words, in order to prevent deformation of the support member, an appropriate strength of the support member need be ensured; accordingly, the border of the opening portion is apt to be widened. In particular, the width of the support member in a direction perpendicular to an alignment direction of the recording heads cannot be shortened; as a result, it has been difficult to shorten the width of the recording head unit.